two subnets, one dns server

[boom42]

I have two broadcast domains on my network - one for everything, including the Internet (10.0.11.0/24) and one for storage and backup stuff (172.16.11.0/24) with 10 GbE NICs. The DNS server in opnsense only serves my everything broadcast domain (10.0.11.0/24). How do I set things up so the DNS server serves the storage domain too (172.16.11.0/24)??

[cookiemonster]

Are you using Unbound or Dnsmasq? The main confiuguration page has a drop down to select the interfaces to serve.
Also the DHCPv4 page has a field for the DNS server for each configured interface. You could use the help tooltip there for additional information.

[boom42]

I'm using dnsmasq. I don't have 172.16.11.0/24 set up in opnsense in any way - I simply manually assign 10 GbE NICs 172.16.11.0/24 IP addresses and nothing else. How do I set up up so 172.16.11.0/24 devices look to dnsmasq running on opnsense for DNS stuff for 172.16.11.0/24 hosts??

[cookiemonster]

You might need to set dnsmasq to forward dns queries but I use Unbound. Further, is that nic with the 172.16.11.0/24 setup on another firewall?
In any case I don't understand your setup. Specifically how can assign an ip address to it and not setup in OPNSense. Maybe if you describe your setup it will be easier to advise.

[boom42]

No, 172.16.11.0/24 is not connected to opnsense or another firewall at all (interfaces nor VLANs) - I simply manually assign static IP addresses to server NICs that I want to use my storage/SAN/NAS server. I basically want to utilize DNS for the 172.x.x.x domain like I currently do with the 10.x.x.x domain and have one DNS server serving both domains. So for example, hostname "funserver01" points to 172.16.11.10 and "funserver01-mgmt" points to 10.0.11.10 and requesting device can access either domain.

Right now I have one 1GbE port/interface (WAN) connected to the ISP modem and the other 1GbE port/interface (LAN) connected to the 48 port 1/10GbE switch. I can add a dual port 10GbE NIC to the opnsense firewall if required.

[cookiemonster]

Let me see if I follow then. You have OPN and your LAN on it serves the 10.0.11.0/24 network segment.
Then also you have a machine in the same network where you assign it a static ip on the machine itself of 172.16.11.X . I say the same network because unless you describe or depict the setup, then this machine's NIC I assume plugs into the same switch that makes up the OPN LAN.
If that's the case then contrary to what you think, you don't have two broadcast domains, only  one. The one setup in OPN.